Hello everyone who can help me. I have ordered a pioneer head unit for my 2001 Magna TJ and recently have taken out the old HU. Attached to the back of the HU was a 14 pin plug which I know has speaker wiring, power etc. an antenna cable and a 8 pin plug.

The 8 pin plug seems to only have one blue wire coming through it. What does this plug do? When I get my new HU, is this wire something I need to connect to? (is it important)

Also can someone recommend a good ground since I have heard that the magna doesn't have one (other than the chasis).

I have linked to a picture of the two plugs. Hope you can help.
http://yfrog.com/j612072010002qj

If it doesn't work link is http://yfrog.com/j612072010002qj

Could be a remote wire, if you have a multimeter check is with the ignition off and on and see if you get a 12v reading

So if it is a remote wire, then i can just leave it because I don't want to connect an amp to my new headunit and I suppose the new headunit would have a different plug or whatever to connect a remote wire to anyway.

You really need to check it with a multimeter or someone with a TJ repair manual can help you with the wiring colours.

If on the 14 pin you have a ,red (ign) yellow (batt), black (gnd) then all you need are the speaker wire colours and if at that point you still dont need to blue one dont use it.